The compound (3.beta.,5.alpha.)-3-hydroxycholest-8(14)-en-15-one is a known hypolipidemic agent (U.S. Pat. No. 4,202,891) which has the structure: ##STR1##
A method of preparing the subject compound from (3.beta.,5.alpha.)-3-(benzoyloxy)cholest-8(14)en-15-one (prepared according to the technique of J. C. Knight et. al., J. Biol. Chem., Vol. 241, p. 1502 (1966)) is disclosed in Example 1 of U.S. Pat. No. 4,202,891. The current procedure for the large scale production of (3.beta.,5.alpha.)-3-hydroxycholest-8 (14)en-15-one essentially follows the stepwise synthetic route described hereinabove with the exception of the final step as shown in Scheme I. ##STR2##
In accordance with Scheme I, isomerization of 5,7-cholestadien-3.beta.-ol benzoate (I) with hydrogen chloride gas in chloroform gives the compound (3.beta.,5.alpha.)- cholesta-7,14-dien-3-ol benzoate (2). Then epoxidation of (2) with m-chloroperbenzoic acid in diethyl ether in the presence of solid sodium bicarbonate in the cold gives the epoxide (3.beta.,5.alpha.,15.alpha.)-14,15-epoxycholest-7-en-3-ol benzoate (3). The epoxide (3) is dissolved in ethanol and water. Then sulfuric acid is added, followed by heating at the reflux temperature for 24 hours to give the crude product (3.beta.,5o)-3-hydroxycholest-8(14)en-15-one (7). The product (7) is recrystallized twice from methanol/heptane/water.